1. Field of the Invention
This invention relates to the field of read/write magnetic head arm assemblies for disk drives data storage systems.
2. Statement of the Problem
In magnetic disk drives, a plurality of magnetic disks are rotated about a common spindle while a plurality of read/write magnetic heads are positioned adjacent the disks to read/write data on the disks. The read/write heads are typically mounted on head arm assemblies which in turn are attached to an actuator. The actuator positions the heads adjacent different tracks on the disks. The positioning of the read/write heads adjacent the disks requires a precision on the order of 10 micro inches In previous devices, the head arm assemblies are typically mounted to the actuators by a plurality of screws.
The use of a plurality of screws to mount the head arm assemblies on the actuator creates a number of problems The screws, in the process of inserting and tightening, can generate debris contamination. Due to the nature of magnetic disk drives, contamination can affect the performance of the data storage on the disks as well as the precision of the positioning of the heads relative to the disks. The screws may not be properly torqued, thus affecting uniform loading on the head arm assemblies. The screws may loosen during the life of the operation of the disk drive, which may damage or cause misalignment of the device. The screws may not seat properly, or may not seat the head arm assemblies properly, thus causing misalignment of the read/write heads.
The arm design used with the screw attachments is not self-aligning, thus increasing costs of assembly. The use of a plurality of screws adds mass to the actuator. Other problems arising with the use of a plurality of screws to fasten the head arm assembly to the actuator include susceptibility to thermal distortion and warpage due to use and low damping capability.
The use of screw attachments created a rigid structure which did not allow for tolerance stackups.
Thus, the need exists for a head arm assembly which is attachable to an actuator without the need for a plurality of screws. There is a further need for a head arm assembly which is self-aligning and does not significantly increase the mass of the actuator.
3. Solution to the Problem
These and other problems are solved by the present invention. The present invention provides a spring mounted head arm which requires few or no screws to attach the head arm assembly to the actuator.
The present invention provides a head arm assembly which is self-aligning relative to the actuator.
The present invention provides a head arm assembly which minimizes distortion due to temperature rise and use.
The present invention provides a head arm assembly which is uniformly loaded by the attachment to the actuator.
The present invention provides a head arm assembly using a resilient force which compensates for tolerance stackups.